Bottom hole pump



Max-c1131, 1964 A. D. LARsoN BOTTOM HOLE PUMP 3 Sheets-Sheet 1 FiledMalrOh 29, 1961 v W. mm m o um. w w v\ @E T/- a S y W, a nu Q M/ M M Y Y7 E //M \M/w B L\ .A V ,5/ QU; T M. 3 4 9... 2 ///J 2 lo 6| |V1 ...l 2 35. M. .0.. .l .0.. F rl' F H March 3'1, 1964 A. D. LARsoN 3,126,836

BOTTOM HOLE PUMP Filed Manch 29, 1961 3 Sheets-Sheet 2 Fg.4 i" 37 7r yi/ y: n j i i 52 f f?. z

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Albert D. Larson IN VEN TOR. 62` BY awaa'm 7`7 d IWW M@ March 3l, 1964A. D. LARsoN 3,125,836

` BOTTOM HOLE PUMP Filed March 29, 1961 5 Sheets-Sheet 3 Fig. 5

A/berf D. Larson lN VEN TOR.

38 Y kwa/lfm United States Patent O 3,126,836 BOTTM HLE PUMP Albert D.Larson, 3025 Chapel Hill Road, Oklahoma City, Okla. Filed Mar. 29, 1961,Ser. No. 99,202 2 Claims. (Cl. 193-179) This invention comprises a noveland useful bottom hole pump and more particularly relates to a deep wellreciprocating pump adapted to effect an increased delivery of fluid fora given size of pump.

The primary object of this invention is to provide a deep wellreciprocating pump which will enable a reduction of the load imposedupon the sucker rod string and the pump jack by the weight of the liuidcolumn being pumped.

A more specific object in accordance with the preceding object is toprovide a device wherein a given sucker rod string and pump jack shallbe capable of lifting a greater quantity of fluid with the same loadthereon or conversely whereby the same amount of fluid may be liftedwith less load upon the sucker rod string and pump jack. The attainmentof this object enables the pumping operation to be performed on a givenquantity of fluid with smaller rods and jack; with the use of lesspower; and with a lower cost of installation, upkeep and operation.

More specifically it is an important object of this invention to providea deep well reciprocating pump having a piston assembly with an upperportion together with a lower portion of a relatively greater area thansaid upper portion in the same tubing string together with means whicheffect a transfer of a portion of the load of the fluid column to thelower portion.

Yet another object of the invention is to provide an irnproved positivesealing means between the pump and the tubing and between the upperpiston portion and the upper cylinder of the pump.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like part throughout, and in which:

FIGURE 1 is a view in vertical section, parts being broken away, andshowing a typical deep well pumping installation with a tubing stringthrough which the pumped fluid flows inserted within the well casing ofa well bore, the installation being a typical one for carrying out theprinciples of this invention, with parts being broken away;

FIGURES 2-5 are views in vertical central section taken upon an enlargedscale through the cased well and tubing assembly and the sucker rod andpump assembly therein, these views being taken along the sectionsindicated by the brackets FIGURE 2, FIGURE 3, FIGURE 4 and FIGURE 5,respectively, of FIGURE l; and

FIGURES 6 and 7 are horizontal sectional Views taken substantially uponthe planes indicated by the section lines 6-6 of FIGURE 2 and 7 7 ofFIGURE 5 respectively.

Referring first to FIGURE l it will be observed that the numeral 10indicates a well bore extending through a formation 12 into a productivezone 14 from which it is desired to pump the well fluid. Shown at 16 isa casing for the well bore 1li although it may be understood that insome instances the casing is not necessary for the successfulapplication of this invention. Shown at 18 is a string of tubing whichextends to the surface of the ground and by means of which the pumpapparatus of this invention is housed and the flow of the pumped fluidto the surface of the ground from the well bore is effected. Inasmuch asthe use of a tubing string for this dual purpose cil er' lCe is wellknown, a further description of the same is deemed to be unnecessary.

It will be understood as set forth hereinafter that the tubing stringitself is slightly modified by incorporating therein a series ofspecifically arranged adapters as at 2t), 22 and 24 whichcooperate withthe structure of the pump as set forth hereinafter.

Using FIGURE l for the purpose of orientation, and referringspecifically to the enlarged detail views of FIG- URES 2-5, it will beseen that there is provided within the tubing string and cooperatingtherewith a deep well reciprocating pump whose construction andoperation form the subject matter of the present invention.

As shown in FIGURE 2, the lowermost section of a sucker rod string asindicated by the numeral 26 is detachably secured as by threadedengagement with the neck 28 of a coupling member 30 to the externallythreaded upper end of a hollow sleeve 32 comprising the upper portion ofthe piston of the pump mechanism. The pump piston upper portion 32 is ahollow sleeve whose open upper end communicates with the hollow interiorof the coupler 30 there being provided ports 34 in the latter whichconstitute the discharge ports for the upper piston portion and whichcommunicate the interior of the upper portion with the interior of thetubing string 1S. It is by means of the annular space between the suckerrod string 26 and the tubing string 18 that the pumped uid is dischargedfrom the well bore to the surface.

As shown in FIGURE 2, the tubing string i8 includes between the twoadapter couplers 20 and 22 a tubing string section 36 which alsocomprises the jacket of the stationary pump barrel in which the pumppiston upper portion reciprocates. Referring further to FIGURE 5 it willbe seen that the adapter coupler 24 attached to the lower extremity ofthe tubing string 1S in turn secures thereto a tubing seating shoe 3Shaving in its upper end a conical internal seating surface 40. As so fardescribed it will now be apparent that the tubing string consisting ofthe previously mentioned connected sections is hollow and open from itslower end at the tubing seating shoe to the surface of the ground atwhich the tubing string terminates.

Stationarily but removably seated in the tubing string is a pump barrelassembly which includes a plurality of interconnected elements of specicdesign and is normally seated in the tubing string upon the tubingseating shoe except that it may be removed from time to time as requiredfor servicing or for other purposes. The stationary pump barrel assemblycomprises as shown in FIG- URE 2 a sleeve 42 which comprises a combinedguide and iishing neck whereby the stationary pump barrel assembly maybe lowered into and seated on the tubing string or removed therefrom.This sleeve 42 has slidably received therethrough with a snug sliding tthe previously mentioned upper piston portion 32. Immediately below andcarried by the combined guide and fishing neck 42 is a cylindrical body44 which comprises a packing arbor for receiving thereon a plurality ofsuitable packing cups or sealing rings 46 which rub against and have afluid tight engagement with the internal surface of the previouslymentioned pump barrel jacket 36. These sealing elements are retainedupon the packing arbor or body 44 as by means of a screw threadedlyengaged adapter and connector 48 which is screw threadedly engaged uponthe lower end of the body 44 as shown in FIGURE 2. Screw threadedlyengaged upon the lower end of the adapter or connector 4S is the upperend of the upper pump barrel jacket 50, see FIGURE 3, in which isreceived and clamped the upper pump barrel S2 in the form of a sleevewhose upper end is sealingly engaged as by a packing ring 54 against theunderside of the connector 48, and whose lower end is similarly engagedand retained by a packing ring 56 which is held in place by a furtheradapter or connector 5S which is internally threadedly engaged in thelower end of the jacket 5t?. The pump barrel 52 has a snug uid tightsliding it with the exterior surface of the cylindrical and tubularupper portion 32 as clearly shown in FIGURE 3.

Threadedly engaged upon the lower end of the connector 53 is aconnecting sleeve 66 which in turn is engaged with the upper end of thelower pump barrel 62. The lower pump barrel is of greater internaldiameter than the upper pump barrel and at its lower end, as shown inFIGURE 5, is threaded to a connector sleeve 64 whose lower end in turnis threadedly engaged upon a sleeve 66 which constitutes the standing orstationary valve cage, this sleeve in turn carrying a coupler 68 inwhich is received the pump seat mandrel lll having thereon a cylindricalpump seat gland 72. lt will be observed that the entire weight of thepump organization is supported upon the pump seating surface All) of thetubular seating sleeve 33 by engagement of the pump seat gland 72 uponthe surface du.

With continuing reference to FlGURE 5 and also to FIGURE 7 it will beobserved that the standing valve cage 66 has a spider 7d therein whichlimits upward travel of the ball valve 76 in the valve chamber 78, thevalve cooperating with an annulus or ring 3@ comprising a valve seatwhich is retained within the open lower end of the valve cage 66 by thescrew threaded engagement of the upper extremity S2 of the connector 68.The latter also has radially extending ports 34 therethrough whichestablish communication from the interior of the stationary pump barrelassembly to the annular space between the latter and the tubing 18, thisannular space still further having communication with the exterior ofthe tubing and the interior of the well casing by means of ports, seeFGURE 3, shown at 86 in the pump barrel assembly and at S8 in the tubingstring 18. Thus, the well fluid rising within the well bore casing andbetween the latter and the tubing string 18 is at all times in freecommunication with the annular space between the stationary pump barrelassembly and the tubing string and through the ports S3, 86 and 811 withthe interior of the pump barrel assembly. The liquid level of the fluidstanding within the well bore and the well casing is indicated in FIGURE2 by the numeral 9@ and it will be understood that the major portion ofthe pump barrel and piston assemblies lie below this liquid level.

Attention is now directed to FIGURES 2-5 for an understanding of theconstruction of the pump piston upper and lower portions and theircooperation with the upper and lower pump barrel assemblies. Aspreviously mentioned, the upper piston portion 32 is directly connectedto the sucker rod string for reciprocation thereby, and extendsdownwardly through the upper barrel assembly in a sliding liuid tightengagement therewith and to all practical purposes may consist of asingle unitary tubular pipe or sleeve extending through the lengthindicated in FIGURES 2 and 3 until its lower end is threadedly engagedin a connecting joint at 1li@ as shown in FlGURE 4. Connected to andsupported by the connector 16) is a cylindrical element 102 or lowerpiston portion comprising a continuation of the upper piston portion 32and which as shown in FIG- URE 5 is screw threadedly engaged upon theinterior surface of the upstanding sleeve 19d of a further connector166. Upon the exterior surface of the sleeve 164i is threadedly engagedan upstanding sleeve 1198 which comprises with the sleeve 192 and theconnector 1M- the lower portion of the pump piston assembly. As will beapparent from FIGURE 4, the major portion of the lower portion sleeve1618 has a uid tight t'it with the interior of the lower pump barrel 62for sliding therein.

Also carried by the lower end of the connector 10o by a screw threadedengagement is the traveling Valve cage 119 which likewise is Yin theform of a sleeve having a valve retaining spider 112 wherein togetherwith a valve chamber 114 in which is received a ball valve 116. Thisvalve cooperates with a valve annulus or seat 118 retained by the screwthreaded gland 12@ therein.

The foregoing completes the structure of this reciprocating type deepwell pump. As so far described it will now be appreciated that thereciprocating elements of this pump include the upper portion 32, theconnector securing the upper portion to the lower portion with thelatter consisting of an inner sleeve 162 and an outer sleeve 163, thetwo sleeves of the lower portion at their lower ends being securedtogether by the connector element 166 which latter in turn carries thetraveling valve cage for reciprocation therewith. Fluid can thus enterthe hollow upper portion upon its downstroke by lifting and unseatingthe traveling valve 116 and passing upwardly into the hollow interior ofthe valve cage,

- through the connector 106, the lower portion inner sleeve 162, theconnector 166 and the upper portion 32 from whence this fluid can emergethrough the ports 34.- into the interior of the tubing string above thepacking means formed by the liuid tight sliding engagement of themembers d6 with the tubing section 36 at the upper end of the pumpbarrel assembly.

The stationary barrel assembly of this pump includes the connector andfishing neck 42, the packing arbor or body 414 with the packing orsealing elements 46 carried thereby, the adapter or connector 48, theupper pump barrel jacket 56 with the upper pump barrel 52 therein, theupper and lower packing rings 54 and 56, the adapter 58, the connectingsleeve 6@ and the lower pump barrel 62 carried thereby, the lower pumpbarrel connector sleeve 64, the stationary or standing valve cage 66,the connector 68, the pump seat mandrel '70 and the pump seat gland 72by which the entire pump barrel assembly is supported upon the tubingstring upon the seating surface du of the tubing seating shoe 38.

The operation of this pump is as follows. With the pump positionedwithin the tubing string the lluid accumula 'ng in the well bore willstand at its natural level as indicated at @il thus immersing the lowerportion of the pump barrel assembly. The registering ports 88 and 86 inthe tubing string and in the pump barrel assembly serve to maintain thepressure of this standing lluid in the well bore in communication withthe annular space lying between the plunger and the pump barrelassemblies and above the lower piston portion 162 and below the packingmeans 46, and further through the annular space lying between the lowerportion 162 and the lower pump barrel 62 and the ports 84 with theinterior of the lower barrel below the standing valve 76. Upon eachupstroke of the piston assembly, therefore, the well iiuid is drawn intothe chamber lying between the two valve assemblies and within the lowerpump barrel. The volume displaced by this upward travel of the upperpiston portion 32 constitutes the volume of fluid delivered at eachworking stroke of the reciprocating pump. This incoming charge of uidpasses the standing check Valve 76 by lifting the latter until thischamber is filled. Upon the following down stroke of the upper plungerassembly, the standing valve '76 will be closed and the liuid withinthis chamber will bypass the traveling valve 116 and move up into theinterior of the hollow upper plunger, filling the latter and passing outthrough the ports 34 at the upper end of the upper plunger into thetubing string.

lt is to be particularly noted that by this construction the eliectivearea of the upper piston portion 32 is substantially one-half that ofthe lower piston portion 1132 inasmuch as the external diameter of thelower outer sleeve 166 and the connection of the connector 106 with theouter sleeve 1% and the inner sleeve 162 of the lower piston portioncomprises an effective working area of the lower portion which issubstantially twice that of the upper portion.

As a result of this arrangement, and of the iluid tight sealingengagement between the pump barrel with the tubing by means of the sealmembers 44, 46, the column of fluid lifted by the pump and which liesabove the liquid level 90 in the well bore thereby lessen the powerrequired to eiect the downward delivery stroke of the pump. Upon thedown stroke of the pump, the weight of the column upon the upper pistonportion assists in effecting the downward stroke. In the operation ofthe present invention, about one-half of the fluid column weight istransferred from the piston portion 32 to the top of the stationary partof the pump barrel assembly. This transfer of weight is accomplished bythe lower piston portion 102 being of a cross sectional area double thatof the upper portion 32. The lower portion, when stroked upward, createsa void between the standing and traveling valve assemblies '76, 116equal to its cross sectional area times the length of its stroke. Thisvoid is illed by incoming fluid from the bore hole and this is theamount of iluid pumped on each stroke of the pump, and since theannulus, between the upper portion and the bore of the lower cylinder orbarrel is not subjected to the iluid column pressure within the tubingstring because of the provision of the sealing or packing members 44, 46previously described, but is subjected only to the bore hole pressure ofthe fluid level 90 through the ports 88, S6, it results on the up strokethat the bore hole pressure pushes against both the bottom and theannulus at the top of the lower piston portion and the fluid columnpressure pushes against the top of the smaller upper portion 32. On thedown stroke, the uid trapped in the larger lower cylinder is forcedupwardly through both the lower and upper piston portion into the tubingstring through the ports 34 above the sealing means 44, 46.

Some of the sucker rod string weight is used to lift the extra iluidbrought into the lower cylinder below the lower piston portion. This maybe calculated as follows: on the down stroke of the piston assembly thecross sectional area of the lower piston portion minus the crosssectional area of the upper piston portion times the fluid columnpressure equals the rod string weight employed to force the pistonassembly down and deliver the trapped fluid up through the pistonassembly and into the tubing.

This action is made possible by the seal between the tubing and themembers 44, 46 at the top of the pump assembly and the seal between theupper piston portion 32 and upper cylinder. By means of the port holesystem, the bore hole iluid can pass into the top of the lower cylinderon the down stroke and on the up stroke this lluid can pass back outthrough the port holes into the bore hole.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention asclaimed.

What is claimed as new is as follows:

l. A reciprocating bottom hole pump assembly comprising a tubing stringopening at its lower end into the bottom of a well bore, a stationarypump barrel assembly in said tubing string and having its lower endopening into said well bore, sealing means establishing a iluid tightseal between the tubing string and said barrel assembly intermediate theends of the latter, a tubular pump plunger assembly slidably disposed inand having a fluid tight seal with said barrel assembly, said plungerassembly including an upper plunger and a lower plunger of greatereffective cross sectional area than that of the former, said upperplunger having continuous communication between its interior and theinterior of said tubing string above said sealing means, a travelingvalve assembly at the lower end of said lower plunger allowing flow ofWell uid upwardly only into the interior of said plunger assembly, astanding valve assembly in said pump barrel assembly below saidtraveling valve assembly and allowing ilow of well iluid from theinterior of said pump barrel assembly upwardly only to said travelingvalve assembly, means establishing continuous communication between saidinterior of said barrel assembly below said standing valve assembly andthe space between said barrel assembly and said tubing string below saidsealing means and between the latter and said well bore, a connector, apair of concentric sleeves secured to the upper end of said connectorand forming said lower plunger, the inner of said concentric sleevesbeing secured to the lower end of said upper plunger.

2. A reciprocating bottom hole pump assembly comprising a tubing stringopening at its lower end into the bottom of a well bore, a stationarypump barrel assembly in said tubing string and having its lower endopening into said well bore, sealing means establishing a iiuid tightseal between the tubing string and said barrel assembly intermediate theends of the latter, a tubular pump plunger assembly slidably disposed inand having a fluid tight seal with said barrel assembly, said plungerassembly including an upper plunger and a lower plunger of greatereffective cross sectional area than that of the former, said upperplunger having continuous communication between its interior and theinterior of said tubing string above said sealing means, a travelingvalve assembly at the lower end of said lower plunger allowing flow ofwell fluid upwardly only into the interior of said plunger assembly, astanding valve assembly in said pump barrel assembly below saidtraveling valve assembly and allowing flow of well fluid from theinterior of said pump barrel assembly upwardly only to said travelingvalve assembly, means establishing continuous communication between saidinterior of said barrel assembly below said standing valve assembly andthe space between said barrel assembly and said tubing string below saidsealing means and between the latter and said well bore, a connector, apair of concentric sleeves secured to the upper end of said connectorand forming said lower plunger, the inner of said concentric sleevesbeing secured to the lower end of said upper plunger, said travelingvalve being carried by the lower end of said connector.

References Cited in the file of this patent UNITED STATES PATENTS2,061,252 Peters Nov. 17, 1936 2,068,729 Basher Jan. 26, 1937 2,166,612Scott July 18, 1939

1. A RECIPROCATING BOTTOM HOLE PUMP ASSEMBLY COMPRISING A TUBING STRINGOPENING AT ITS LOWER END INTO THE BOTTOM OF A WELL BORE, A STATIONARYPUMP BARREL ASSEMBLY IN SAID TUBING STRING AND HAVING ITS LOWER ENDOPENING INTO SAID WELL BORE, SEALING MEANS ESTABLISHING A FLUID TIGHTSEAL BETWEEN THE TUBING STRING AND SAID BARREL ASSEMBLY INTERMEDIATE THEENDS OF THE LATTER, A TUBULAR PUMP PLUNGER ASSEMBLY SLIDABLY DISPOSED INAND HAVING A FLUID TIGHT SEAL WITH SAID BARREL ASSEMBLY, SAID PLUNGERASSEMBLY INCLUDING AN UPPER PLUNGER AND A LOWER PLUNGER OF GREATEREFFECTIVE CROSS SECTIONAL AREA THAN THAT OF THE FORMER, SAID UPPERPLUNGER HAVING CONTINUOUS COMMUNICATION BETWEEN ITS INTERIOR AND THEINTERIOR OF SAID TUBING STRING ABOVE SAID SEALING MEANS, A TRAVELINGVALVE ASSEMBLY AT THE LOWER END OF SAID LOWER PLUNGER ALLOWING FLOW OFWELL FLUID UPWARDLY ONLY INTO THE INTERIOR OF SAID PLUNGER ASSEMBLY, ASTANDING VALVE ASSEMBLY IN SAID PUMP BARREL ASSEMBLY BELOW SAIDTRAVELING VALVE ASSMBLY AND ALLOWING FLOW OF WELL FLUID FROM THEINTERIOR OF SAID PUMP BARREL ASSEMBLY UPWARDLY ONLY TO SAID TRAVELINGVALVE ASSEMBLY, MEANS ESTABLISHING CONTINUOUS COMMUNICATION